The Cerrillos Uplift, the La Bajada Constriction, and Hydrogeologic Framework of the Santo Domingo Basin, Rio Grande Rift, New Mexico Edited by Scott A. Minor Professional Paper 1720 Version 1.0 2007 U.S. DEPARTMENT OF THE INTERIOR DIRK KEMPTHORNE, Secretary U.S. GEOLOGICAL SURVEY Mark D. Myers, Director For more information about the U.S. Geological Survey and its products: Telephone 1-888-ASK-USGS URL: http://www.usgs.gov/ ------------------------------------------------------------------------------------------------- This CD-ROM is a digital edition of Professional Paper 1720, including plates, in Portable Document Format (PDF), as well as GIS files and metadata in support of the geology shown on plate 2. Abstract The geologic, geophysical, and hydrogeologic properties of the La Bajada constriction and Santo Domingo Basin, northern New Mexico, result from tectonic and volcanic processes of the late Tertiary and Quaternary Rio Grande rift. An integrated geologic and geophysical assessment in the La Bajada constriction allows development of a geologic framework that can provide input for regional ground-water flow models. These models then can provide better estimates of future water supplies in a region that largely subsists on aquifers in Rio Grande rift basins. The combination of surface geologic investigations (stratigraphic and structural studies; chapters A, B, C, and E), airborne geophysics (aeromagnetic and time-domain electromagnetic surveys; chapters D and F), ground geophysical measurements (gravity and magnetotelluric surveys; chapters D and F), and data from the few wells in the area (chapter G) provides new constraints on the hydrogeologic framework of this area. Summary results of our investigations are synthesized in chapter G. Through- going aquifers consisting of ancestral Rio Grande axial-river sand and gravel and of coarse western-piedmont gravel form the predominant ground-water pathways through the partly buried structural trough defining the La Bajada constriction between Espaņola and Santo Domingo Basins. Thick, clay-rich Cretaceous marine shales of low hydraulic conductivity form a pervasive regional confining unit within the Cerrillos uplift on the southeast flank of the constriction. Numerous, dominantly north-northwest-striking, intrabasin faults that project part way across the La Bajada constriction create a matrix of laterally and vertically variable hydrogeologic compartments that locally partition and deflect ground-water flow parallel to faults. -------------------------------------------------------------------------------- Disclaimer This Compact Disc-Read Only Memory (CD-ROM) publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Although all data and software published on this CD-ROM have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and (or) the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data, the software, or related materials. -------------------------------------------------------------------------------- Contents of this CD-ROM: This disc contains eight Portable Document Format (PDF) files. These are p1720.pdf, which is the main part of the report, and p1720-pl1.pdf, p1720- pl2.pdf, p1720-pl2(hillshade).pdf, p1720-pl3.pdf, p1720-pl4.pdf, p1720-pl5.pdf, and p1720-pl6.pdf, which are plates 1-6, located in the "plates" folder. Installers for Microsoft Windows 2000 and XP and Mac OS X v. 10.2.8 or higher are in the "Acrobat Installers" folder. All PDF files can be viewed and printed from Acrobat Reader 7.0. This disc also contains GIS files and metadata in support of the geology shown on plate 2. These are in a separate folder called "p1720-GIS," which also includes a 00README file specific to the database. A separate "metadata" folder contains a copy of the metadata for the geology shown on plate 2, as well as metadata in support of geophysical data shown on plates 3 and 4. -------------------------------------------------------------------------------- System requirements for the Adobe Acrobat files: Adobe Reader 7.0 MS Windows Intel Pentium-class processor Windows XP Professional or Home Edition with SP1 or SP2, or Tablet PC Edition; Microsoft Windows 2000 with Service Pack 2 (SP2) 128 MB of RAM 90 MB of available hard-disk space for the full version 800 × 600 monitor resolution Adobe Reader 7.0 Macintosh PowerPC G3, G4, G5 processor Mac OS X v.10.2.8 or 10.3 or higher 128 MB of RAM 80 MB of available hard disk space (110 MB required for the full version) 800 × 600 screen resolution To get started: 1. Install Acrobat Reader 7.0 (included on this disc) on your hard drive if not already installed. 2. From within Acrobat Reader, navigate to the file p1720.pdf on your CD-ROM drive and open it to view the report. 3. To view the plates, click on a plate title in the main table of contents (p. iii) to open the PDF of that plate. 4. To access the GIS files and metadata in support of the geology shown on plate 2, navigate to the folder "p1720-GIS" and open 00README.TXT for a list of files. To access the metadata in support of geophysical data shown on plates 3 and 4, navigate to the folder "metadata," which includes a copy of the metadata for the geology shown on plate 2 as well. --------------------------------------------------------------------------------